JP2000074128A - Vibration isolating device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the wall thickness of a part of partition member where a high dimensional accuracy is required and suppress drop of the strength of the partition member to be caused by reduced wall thickness. SOLUTION: A partition member 50 installed in a vibration isolating device 40 partitions a liquid chamber 49 into a main liquid chamber 51 and aux. liquid chamber 52, which are put in mutual communication via a restricting passage 65. The partition member 50 is composed of a disc-shaped membrane rubber 55 and a ring-shaped partition periphery 54. The periphery 54 is formed from a resin through injection molding using a die, and inside the partition periphery 54, a tube-form hollow chamber 66 is formed along the peripheral surface in tight attachment to the inside surface of the liquid chamber 49. That part of the hollow chamber 66 which is positioned along the peripheral surface of the partition periphery 54 is formed with a reduced wall thickness, which prevents the accuracy of the outside diameter of the partition periphery 54 from degradation caused by shrinkage when the resin solidifies.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration device applied to a case where transmission of vibration from an engine mounted on a vehicle is suppressed, and a method of manufacturing the same.

[0002]

2. Description of the Related Art As an anti-vibration device applied to a vehicle, for example, an anti-vibration device as an engine mount is disposed between an engine of a vehicle serving as a vibration generating unit and a vehicle body serving as a vibration receiving unit. There is known a device that absorbs vibration generated by an engine by a vibration isolator.

FIG. 10 shows an example of the structure of the above-described vibration isolator. In the vibration damping device 10, a mounting screw 11 for connecting to an engine (not shown) protrudes from a central portion of a mounting bracket 12 on an upper side, and these are used as a first mounting member. On the lower side, a mounting screw 14 is provided at the center of the lid member 13 for connecting and fixing to a vehicle body (not shown).
Are projected, and further around the lid member 13 are collar portions 13.
A is formed, and an outer cylinder 15 is attached to the collar portion 13A, and these are used as a second attachment member. The first mounting member and the second mounting member are connected to the elastic body 16.
The vibration isolator 10 is provided with a liquid chamber 17 whose volume changes due to deformation of the elastic body 16.
A disk-shaped partition member 18 is disposed inside the liquid chamber 17, and the partition member 18 presses the outer peripheral surface thereof against the inner peripheral surface of the liquid chamber 17 so that the liquid chamber 17 is separated from the main liquid chamber 19. The sub-liquid chamber 20 is defined. Further, as shown in FIG. 11, the partition member 18 is provided with a restriction passage 21 for communicating the main liquid chamber 19 and the sub liquid chamber 20, and as shown in FIG.
Below the metal member 8, a metal stopper 32 is arranged.
When the engine mounted on the vehicle is operated to generate vibration, the vibration damping function of the elastic body 16 and the viscous resistance or the liquid column of the liquid in the restriction passage 21 communicating these liquid chambers 19 and 20 are provided. Vibration is absorbed by resonance or the like, and vibration transmitted to the vehicle body is suppressed.

The partition member 18 includes a disk-shaped membrane rubber 22 disposed at the center and a partition outer peripheral portion 23 integrally formed of resin so as to embed the peripheral portion of the membrane rubber 22. Have been. The partition outer peripheral portion 23 is formed by a mold 24 which is a resin molding mold as shown in FIG. The mold 24 includes an upper mold 25, a lower mold 26, and split dies 27A and 27B. The membrane rubber 22 is loaded so as to be sandwiched between the split dies 25 and 26 before molding. In this state, the resin material heated and melted is injected from the gate 28 into the cavity 29 of the mold 24, and the resin material is solidified in the cavity 29, whereby the partition wall outer peripheral portion 23 is formed. As a result, the peripheral edge of the membrane rubber 22 is embedded in the partition outer peripheral portion 23, and the membrane rubber 22 and the partition outer peripheral portion 23 are joined so as to be structurally integrated, and the partition member 1
8 had been manufactured.

However, in the case where the partition outer peripheral portion 23 of the partition member 18 is formed by injection molding of a resin into a mold 24,
The cooling rate of the molten resin is high near the contact surface with the mold 24, and the cooling rate decreases as the distance from the mold 24 increases. There is a problem that accuracy is reduced.
For example, when the dimensional accuracy of the outer peripheral surface of the partition outer periphery 23 decreases due to such sink marks, a liquid leaks from between the outer peripheral surface of the partition outer periphery 23 and the inner peripheral surface of the liquid chamber 17, and the liquid viscous resistance and the like. There is a possibility that the damping effect due to this may be reduced. For this reason, in the conventional vibration isolator 10, as shown in FIG.
0 is formed so that the outer peripheral surface of the partition outer peripheral portion 23 is formed with required dimensional accuracy. Here, meat soak 30
Is a notch 2 that allows the restriction passage 21 to communicate with the main liquid chamber 19.
It is formed along the outer peripheral surface of the partition outer peripheral portion 23 except for the vicinity of 1A. By reducing the wall thickness of the portion along the outer peripheral surface of the partition outer peripheral portion 23 by the thickness reduction 30, the influence of sink in the solidification process is suppressed, and the dimensional accuracy of the outer peripheral surface of the partition outer peripheral portion 23 is ensured. I have.

[0006]

[0005] In many cases, the shape and dimensions of the underfill 30 formed on the outer peripheral portion 23 of the partition wall are determined by trial and error based on past empirical and experimental data. I can decide. This is the partition outer peripheral portion 23.
It is relatively easy to design the underfill 23 only for the purpose of improving the dimensional accuracy of the outer peripheral surface of the partition wall, but a liquid pressure that periodically changes due to external vibration acts on the partition outer peripheral portion 23. Therefore, it is necessary to provide a strength that can sufficiently oppose the liquid pressure. In order to satisfy both of the conflicting factors of securing the dimensional accuracy and securing the strength of the outer peripheral portion 23 of the partition wall, the shape and dimensions of the underfill 30 are changed stepwise little by little, and required after many molding processes. Trial and error were required to determine the shape, dimensions, and the like of the fillet 30 to satisfy both the required dimensional accuracy and strength.

[0007] The cavity 29 of the mold 24 is
As shown in FIG. 2, it is necessary to form a convex portion 31 having a shape corresponding to the thickness reduction 30 of the partition outer peripheral portion 23. The optimum shape of the thickness reduction 30 is determined by changing manufacturing conditions, for example, by changing the mold 24.
Changes due to slight changes in the temperature of the molten resin injected into the mold, the components of the resin material, etc., so that each time these manufacturing conditions are changed, it is necessary to change the design of the mold 24, or these manufacturing conditions Different types of dies 24 for different products
Is required. For this reason, there is a problem that the cost of the vibration isolator 10 cannot be reduced.

In view of the above facts, the present invention provides a vibration damping device which enables a portion of the partition wall member requiring high dimensional accuracy to be thinned and suppresses a decrease in strength of the partition wall member due to the thinning. It is another object of the present invention to provide a method of manufacturing a vibration isolator capable of forming a thick portion of a partition wall member with high dimensional accuracy without changing the shape of a mold for injection molding.

[0009]

According to a first aspect of the present invention, there is provided a vibration isolator connected to one of a vibration generating section and a vibration receiving section, and connected to the other of the vibration generating section and the vibration receiving section. A second mounting member, an elastic body connecting the first mounting member and the second mounting member, and a liquid in which at least a part of an inner wall is formed of the elastic body and a liquid is sealed. A chamber formed at least of an outer peripheral portion with a resin, and a hollow chamber extending along an inner wall of the liquid chamber is formed in the outer peripheral portion, and the outer peripheral portion is brought into close contact with an inner wall of the liquid chamber to form the liquid chamber. A partition member partitioned into a main liquid chamber whose internal volume changes due to deformation of the elastic body and a sub liquid chamber adjacent to the main liquid chamber, and a restricting passage communicating the main liquid chamber and the sub liquid chamber. .

According to the vibration damping device having the above-mentioned structure, at least the outer peripheral portion of the partition member is formed of a resin material, and a hollow chamber is formed inside the outer peripheral portion along the inner wall of the liquid chamber. Since the outer peripheral portion is thinned by the hollow chamber, when the outer peripheral portion of the partition member is molded by molding, the dimensional accuracy of the outer peripheral portion of the partition member can be prevented from being reduced due to the influence of sink during solidification of the resin material, In addition, as compared with the case where a thin portion such as a groove shape is formed in the outer peripheral portion of the partition member, the opening area to the outer surface of the partition member can be reduced according to the hollow chamber, so that a decrease in the strength of the outer peripheral portion of the partition member can be suppressed. . As a result, the sealing property between the inner wall of the liquid chamber and the outer peripheral portion of the partition member is improved, so that liquid leakage from the main liquid chamber and the sub liquid chamber is prevented.

According to a second aspect of the present invention, there is provided a method of manufacturing a vibration isolator, wherein the first mounting member is connected to one of the vibration generating section and the vibration receiving section, and the first mounting member is connected to the other of the vibration generating section and the vibration receiving section. 2
A mounting member, an elastic body connecting the first mounting member and the second mounting member, and a liquid chamber in which at least a part of an inner wall is formed of the elastic body and in which a liquid is sealed,
A partition member that is divided into a main liquid chamber and an auxiliary liquid chamber adjacent to the main liquid chamber, the inner wall of which is brought into close contact with the inner wall of the liquid chamber and whose liquid volume changes by deformation of the elastic body; A method for manufacturing a vibration isolator having a restricted passage communicating the main liquid chamber and the sub liquid chamber, the method being equivalent to an outer shell portion of the partition member after injecting a heated and melted resin material into a mold. A pressurized gas is blown into the molten layer inside the skin layer to form a hollow chamber extending along the inner wall of the liquid chamber in the partition member.

According to the method of manufacturing the vibration isolator of the above configuration,
Injecting the heat-melted resin material into the mold to form a skin layer of the partition member, blowing a pressurized gas into a molten layer inside the skin layer, and extending the partition member along the inner wall of the liquid chamber. By forming the hollow chamber, the outer peripheral portion of the partition member is thinned by the hollow chamber, and the skin layer of the partition member is pressed against the inner surface of the mold by the pressurized gas blown into the hollow chamber, In this state, the solidification of the resin material inside the skin layer proceeds, so that the dimensional accuracy of the outer peripheral portion of the partition member can be prevented from being reduced by the influence of sink during solidification of the resin material, and the outer peripheral portion of the partition member is molded. Can be molded into a shape that exactly corresponds to the cavity shape of

Here, the skin layer of the partition member is a solidified layer of the resin material solidified in a film form relatively early after the start of the injection molding of the molten resin material, starting from the contact surface with the mold. A molten layer in which a resin material in a molten state is sealed is formed inside the skin layer.

According to a third aspect of the present invention, the vibration isolator is connected to one of the vibration generating section and the vibration receiving section, and is connected to the cylindrical outer cylinder and the other of the vibration generating section and the vibration receiving section, And an inner cylinder disposed inside the outer cylinder, an elastic body disposed between the outer cylinder and the inner cylinder, and a liquid filled with the elastic body as a part of a partition wall, and an elastic body A main liquid chamber whose internal volume changes due to deformation, a sub liquid chamber which is isolated from the main liquid chamber and in which a liquid is sealed, isolates the main liquid chamber and the sub liquid chamber, and A restriction passage communicating with the sub liquid chamber is provided, and a partition member having a valve element storage chamber formed in the middle of the restriction path, and the main liquid chamber and the sub liquid chamber inserted into the valve element storage chamber and A valve body for controlling the flow of liquid between the valve member, wherein at least the valve body in the partition member Around the accommodated chamber is molded of a resin material, and forming a hollow chamber in the vicinity of the valve body accommodating chamber in the interior of the partition member.

According to the vibration damping device having the above structure, at least the peripheral portion of the valve element storage chamber in the partition member is formed of a resin material, and the hollow portion adjacent to the valve element storage chamber is formed in the peripheral portion of the valve element storage chamber in the partition member. By forming the chamber, if the hollow chamber is formed in the thick part in the peripheral part of the valve body storage chamber, the thick part in the peripheral part of the valve body storage chamber can be made thinner by the hollow chamber. When the periphery of the valve body storage chamber of the member is molded by molding, it is possible to prevent the dimensional accuracy of the valve body storage chamber from being reduced by the influence of sink during solidification of the resin material, and to the periphery of the valve body storage chamber. Since the opening area to the outer surface of the partition member can be reduced as compared with the case of forming a bulge such as a groove shape, a decrease in the strength of the peripheral portion of the valve element storage chamber can be suppressed. As a result, the sealing performance between the valve element storage chamber and the valve element is improved, and liquid leakage from between the valve element storage chamber and the valve element is prevented.

According to a fourth aspect of the present invention, there is provided a method for manufacturing a vibration isolator, comprising: an outer cylinder connected to one of a vibration generator and a vibration receiver and formed into a tubular shape; and the other of the vibration generator and the vibration receiver. An inner cylinder connected and arranged inside the outer cylinder, an elastic body arranged between the outer cylinder and the inner cylinder, and a liquid filled with the elastic body as a part of a partition wall, and A main liquid chamber whose internal volume changes due to deformation of an elastic body, a sub liquid chamber which is isolated from the main liquid chamber and in which a liquid is sealed, and which separates the main liquid chamber and the sub liquid chamber from each other; A restriction passage communicating the liquid chamber and the sub liquid chamber is provided, and a partition member having a valve body storage chamber formed in the middle of the restriction passage, and the main liquid chamber inserted into the valve body storage chamber and the main liquid chamber and A valve for controlling the flow of liquid between the auxiliary liquid chamber, and a method of manufacturing a vibration isolator,
After injecting the heat-melted resin material into the mold, a skin layer corresponding to the outer shell portion of the partition member is formed, and a pressurized gas is blown into a molten layer inside the skin layer to form an inner portion of the partition member. And a hollow chamber is formed near the valve body storage chamber.

According to the method of manufacturing the vibration isolator having the above configuration,
Injecting the heat-melted resin material into the mold to form the skin layer of the partition member, blowing a pressurized gas into the molten layer inside the skin layer, and hollowing the partition member adjacent to the valve body storage chamber. By forming the chamber, if the hollow chamber is formed in the thick part in the peripheral part of the valve body storage chamber, the thick part in the peripheral part of the valve body storage chamber is thinned by the hollow chamber, and the hollow part is formed. The skin layer of the partition member is pressurized against the inner surface of the mold by the pressurized gas blown into the chamber, and in this state, the solidification of the resin material inside the skin layer progresses. Dimensional accuracy can be prevented from being reduced by the influence of sink during solidification of the resin material, and the valve element storage chamber of the partition member can be formed into a shape exactly corresponding to the cavity shape of the mold.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vibration isolator according to an embodiment of the present invention and a method for manufacturing the same will be described with reference to the drawings. (First Embodiment) FIG. 1 shows a cross section of a vibration isolator according to a first embodiment of the present invention. This vibration isolator 40
A cup-shaped connecting member 4 having one end closed
The connecting member 41 is tapered from the bottom toward the opening. The connecting member 41 has a flange portion 41 </ b> A extending radially at an end on the opening side. A disk-shaped mounting member 42 is fixed to the flange portion 41A of the connecting member 41 by welding or the like. A mounting screw 43 is inserted from below into a through hole provided at the center of the mounting bracket 42, and the screw 43 is fixed to the mounting bracket 42 so that a screw shaft protrudes upward. Screw 4
Reference numeral 3 is used for connecting to one of the vibration generating unit and the vibration receiving unit, and the connecting member 41, the mounting bracket 42, and the screw 43 constitute a first mounting member.

A cover member 44 is disposed below the vibration isolator 40. This lid member 44 is a lid portion 44A on the cup.
And a flange portion 44B which extends radially from the end on the opening side of the lid portion 44A over the entire circumference and has an outer peripheral end portion bent upward. A screw 45 is inserted from above into a through hole provided at the center of the cover 44A, and the screw 45 is inserted into the cover member 44 such that the screw shaft protrudes downward.
It is fixed to. The screw 45 is used to connect to the other of the vibration generating unit and the vibration receiving unit. The lower end of the outer cylinder 46 is fixed to the flange 44 </ b> B of the lid member 44.
The outer cylinder 46 has a lower end portion which is inserted into the outer peripheral surface of the flange portion 44B, and which is caulked so as to clamp the flange portion 44B from above and below, and a substantially cylindrical housing extending upward from the caulking portion 46A. It is formed by a cylindrical portion 46B. A connecting portion 46C is formed at an upper end portion of the storage tube portion 46B so as to expand in a tapered shape outward in the radial direction. The screw 45, the lid member 44, and the outer cylinder 46 constitute a second mounting member.

The connecting member 41 forming the first mounting member and the outer cylinder 46 forming the second mounting member are connected by an elastic body 47. The elastic body 47 is formed in a substantially cylindrical shape having an upper end closed and a lower end opened.
The top of the elastic member 47 is formed to be thicker than the side wall, and a recess 47A corresponding to the shape of the connecting member 41 is formed in the center of the top surface of the elastic body 47. A tapered portion 47B corresponding to the shape of the connecting portion 46C of the outer cylinder 46 is formed on the surface. Here, the connecting member 41 is inserted into the concave portion 47A, and the inner surface of the concave portion 47A is
The outer peripheral surface of the tapered portion 47B is further vulcanized and bonded to the inner peripheral surface of the connecting portion 46C. Thus, the first mounting member and the second mounting member are connected by the elastic body 47, and the opening of the outer cylinder 46 on the tapered portion 47 </ b> B side is closed by the top of the elastic body 47. The outer peripheral surface of the side wall of the elastic body 47 is in close contact with the inner peripheral surface of the outer cylinder 46,
The inner peripheral surface of the outer cylinder 46 is covered by the side wall portion.

A diaphragm 48 made of a film-like elastic material such as rubber is attached to the opening end side of the outer cylinder 46 so as to close the opening of the outer cylinder 46. Thereby, the outer cylinder 4
Inside 6, a closed space is formed by an elastic body 47 and a diaphragm 48, and the closed space is filled with a liquid such as water, oil, ethylene glycol or the like to form a liquid chamber 49. A substantially disk-shaped partition member 50 is disposed in the liquid chamber 49, and the partition member 50 partitions the liquid chamber 49 into two small liquid chambers, a main liquid chamber 51 and a sub liquid chamber 52. ing.

The partition member 50 has a circular opening 53 at the center.
Are formed from a ring-shaped partition wall outer peripheral portion 54 formed with a groove, and a disk-shaped membrane rubber 55 fixed to the partition wall outer peripheral portion 54 so as to close the opening 53. The partition wall outer peripheral portion 54 is made of polyamide resin, ABS, or the like. , Polyacetal, polycarbonate, polyimide and the like. The partition outer peripheral portion 54 can be formed of a thermosetting resin material such as an epoxy resin or a phenol resin, or an elastomer, in addition to the above-described thermoplastic resin. Membrane rubber 55
2B, a thin flange portion 56 is provided over the entire periphery as shown in FIG. 2B, and a rib-like fitting is formed on the flange portion 56 along the outer peripheral end thereof. Part 56
A protrudes upward. On the other hand, in the partition outer peripheral portion 54,
A fitting groove 54 </ b> A corresponding to the fitting portion 56 </ b> A of the flange portion 56 is formed in the peripheral portion of the opening 53. The membrane rubber 55 has a convex central portion inside the flange portion 56A inserted into the opening 53 from the side of the sub liquid chamber 52, and the flange portion 56A.
And the fitting portion 56
A is fitted into the fitting groove 54A.

Below the partition member 50, a metal stopper 57 is arranged as shown in FIG. The stopper 57 is formed by a ring-shaped flange portion 58 and a cup-shaped support portion 59 provided inside the flange portion 58. The stopper 57 is supported by the support 59
Is brought into contact with the lower surface near the outer peripheral portion of the membrane rubber 55 and the upper surface of the flange portion 58 is brought into contact with the lower surface of the outer peripheral portion 54 of the partition wall. Thereby, the membrane rubber 5
5 is fixed to the outer peripheral portion 54 of the partition wall, and the partition member 50 is fixed to a predetermined position in the liquid chamber 49. The diaphragm 48 for closing the opening of the outer cylinder 46 is formed of an elastic body such as rubber, and is formed by a ring-shaped flange portion 60 and a truncated cone-shaped liquid chamber forming portion 61 provided inside the flange portion 60. Is formed. The diaphragm 48 makes the flange portion 60 adhere to the flange portion 58 of the stopper 57 over the entire circumference, and the liquid chamber forming portion 61 makes the stopper 5
7 and the supporting portion 59 of the stopper 57
And a sub liquid chamber 52 is formed between them.

Here, the stopper 57 and the diaphragm 48
Means that the flange portions 58 and 60 are sandwiched between the flange portion 44B of the lid member 44 and the caulked portion 46A of the outer cylinder 46 and are fixed to the outer cylinder 46. Further, an air chamber 62 is formed between the liquid chamber forming portion 61 of the diaphragm 48 and the lid member 44, whereby the diaphragm 48 is formed.
Is possible. The air chamber 62 may communicate with the outside through the lid member 44. Further, the center of the lower surface of the membrane rubber 55 is formed in a concave shape, and a flat liquid chamber having a small dimension in the height direction is formed between the lower surface of the membrane rubber 55 and the upper surface of the support portion 59 of the stopper 57. Is done. A plurality of through holes 59A are formed in the support portion 59 of the stopper 57.
These through holes 59 </ b> A communicate a liquid chamber formed between the membrane rubber 55 and the support portion 59 as a part of the sub liquid chamber 52.

As shown in FIG. 2 (B), the outer peripheral surface 54A of the partition outer peripheral portion 54 has a flat shape extending in the circumferential direction.
A letter-shaped circumferential groove 63 is formed. A notch 64 communicating with the main liquid chamber 51 is formed at one end of the peripheral groove 63, and a notch (not shown) communicating with the auxiliary liquid chamber 52 is formed at the other end of the peripheral groove 63. Have been. The partition outer peripheral portion 54 presses the upper side and the lower side of the peripheral groove 63 on the outer peripheral surface 54A against the inner peripheral surface of the elastic body 47, respectively.
Thereby, the circumferential groove 63 of the partition outer peripheral portion 54 forms a restriction passage 65 together with the elastic body 47 forming the inner wall of the main liquid chamber 51 as shown in FIG. The sub-liquid chamber 52 is communicated.

As shown in FIG. 2, a hollow space 66 is formed inside the outer peripheral portion 54 of the partition wall along the outer peripheral surface 54A. The hollow chamber 66 has a C in plan view from an end 66C near one end of the notch 64 in the circumferential direction to an end 66D near the other end of the notch 64 in the circumferential direction.
A circumferential surface 66A is formed in the hollow chamber 66 so as to be substantially parallel to the outer peripheral surface 54A. In the hollow chamber 66, a gas injection hole 66B penetrating from the inside of the hollow chamber 66 to the upper surface of the partition outer peripheral portion 54 is formed at a central position in the circumferential direction. Therefore, the hollow chamber 66 communicates with the main liquid chamber 51 through the gas injection hole 66B, and the main liquid chamber 5
One liquid is filled.

Next, the vibration isolator 4 configured as described above is used.
The method of manufacturing the partition member 50 at 0 will be described with reference to FIGS. The partition member 50 includes the partition outer peripheral portion 54 and the membrane rubber 55 as described above. When manufacturing the partition outer peripheral portion 54, a membrane rubber 55 formed of an elastic rubber or the like is manufactured in advance by injection molding or the like, and the membrane rubber 55 is set in a mold 67. As shown in FIG. 3, the mold 67 includes a plurality of upper molds 68, a lower mold 69, and split molds 70A and 70B. A gate 72 opened to a position corresponding to the gate 72 is formed. At the time of forming the outer peripheral portion 54 of the partition wall, the membrane rubber 55 is divided into the molds 68 and 69 in the cavity 71.
It is set so that it is pinched by.

As shown in FIG. 3, the membrane rubber 55
Is set in an injection molding machine (not shown). Here, as the injection molding machine, one capable of injection molding by a known gas assist method is used. Such an injection molding machine is capable of controlling the injection of the molten resin into the mold 67 and the injection of the pressurized gas. Can be set, and the injection amount, injection pressure, and the like can be set for the pressurized gas. Here, an inert gas such as nitrogen is used as a gas injected into the mold 67 by the injection molding machine.

As shown in FIG. 4, an injection nozzle 73 for gas assist is connected to the gate 72 of the mold 67 mounted on the injection molding machine. A small-diameter gas injection pipe 74 is disposed inside the nozzle 73, and a resin injection path 75 is formed so as to surround the outer circumference of the gas injection pipe 74. An on-off valve 76 for opening and closing the resin injection path 75 is disposed at the tip of the nozzle 73. A seal ring 77 corresponding to the shape of the tip of the nozzle 73 is fitted into the gate 72 of the mold 67 at the opening end on the resin injection side.

The injection molding machine first opens the opening / closing number 76 and injects the molten resin into the cavity 71 of the mold 67 through the gate 72. At this time, the injection amount of the resin into the mold 67 is
It is determined by the filling rate of the resin with respect to the volume of the cavity 71 set in advance. The resin injected into the cavity 71 begins to solidify from a portion in contact with the inner surface of the cavity 71 by an endothermic reaction by the mold 67, and a skin layer is formed along the inner surface of the cavity 71. This cavity 7
The thickness of the skin layer in 1 increases with time. An unsolidified molten layer is sealed inside the skin layer in the cavity 71.

The injection molding machine injects a pressurized gas into the cavity 71 through the gate 72 at the timing when the skin layer in the cavity 71 has a constant thickness. The pressurized gas flows so as to push the central portion of the molten layer, which is the slowest to solidify, toward the cavity 71 side, thereby forming a tubular hollow chamber 66.
To form The injection molding machine keeps the gas filled in the air chamber at a predetermined pressure until the resin in the cavity 71 is almost completely solidified, and detaches the nozzle 73 from the gate 72 of the mold 67 after the solidification is completed. Thereafter, the mold 67 composed of the molds 68 and 69 and the split molds 70A and 70B is disassembled, so that the partition wall member 50 in which the partition outer peripheral portion 54 and the membrane rubber 55 are integrated can be taken out. A tubular hollow chamber 66 is formed in the partition outer peripheral portion 50 along the outer peripheral surface as shown in FIG.

Next, the operation of the vibration isolator according to the first embodiment of the present invention will be described.

The above-described vibration isolator 40 includes the mounting bracket 4
When an engine (not shown) connected to the first mounting member 2 or the like is operated, vibration from the engine is applied to the mounting bracket 4.
The light is transmitted to the elastic body 47 via the second member 2 and the connecting member 41.
The elastic body 47 acts as a vibration absorbing main body, and can absorb vibration by a vibration damping function based on internal friction when the elastic body 47 is deformed. Further, the liquid in the main liquid chamber 51 and the liquid in the sub liquid chamber 52 flow mutually through the restriction passage 65,
The damping effect based on the viscous resistance of the liquid flow generated inside 5 can improve the vibration isolation effect.

Further, a membrane rubber 55 is attached to the opening 53 of the outer peripheral portion 54 of the partition wall, and the main liquid chamber 51 and the sub liquid chamber 52 are adjacent to each other with the stopper 57 having the membrane rubber 55 and the through hole 59A formed therebetween. Accordingly, even when the restriction passage 65 is clogged and a sufficient vibration damping effect cannot be obtained by the restriction passage 65 alone, such as when high-frequency vibration is transmitted, the membrane rubber 55
Are elastically deformed, and an increase in the internal pressure of the main liquid chamber 51 is suppressed, so that the main liquid chamber 51 and the membrane rubber 55 function as a low dynamic spring, and the vibration isolation effect is maintained.

According to the vibration damping device 40 of the present embodiment described above, the outer peripheral portion 54 of the partition member 50 is formed of a resin material, and the liquid chamber 49 is provided inside the outer peripheral portion 54 of the partition member.
By forming the hollow chamber 66 along the inner peripheral surface of the partition wall, the partition wall outer peripheral portion 54 is thinned by the hollow chamber 66. Therefore, when the partition outer peripheral portion 54 is formed by injection molding, the outer diameter of the partition outer peripheral portion 54 is reduced. The dimensional accuracy can be prevented from being reduced due to the influence of sink during solidification of the resin material, and the opening to the outer surface of the partition outer peripheral portion 54 is smaller than that in the case where a groove-like or the like is formed in the partition outer peripheral portion 54. Since only the gas injection hole 66B is provided, a decrease in the strength of the partition outer peripheral portion 54 can be suppressed. As a result, the sealing performance between the inner peripheral surface of the elastic body 47 forming the inner wall of the liquid chamber 49 and the outer peripheral surface 54A of the partition outer peripheral portion 54 can be improved, so that liquid leakage from the main liquid chamber 51 and the sub liquid chamber 52 can be prevented. Can be prevented.

Further, according to the method of manufacturing the vibration isolator 40 of the present embodiment, the heat-melted resin is injected into the mold 67 to form a skin layer which is an initial solidified layer of the outer peripheral portion 54 of the partition wall. By blowing a pressurized gas (nitrogen) into the molten layer inside the skin layer and forming a hollow chamber 66 in the partition outer peripheral portion 54, the partition outer peripheral portion 54 is thinned by the hollow chamber 66 and is blown into the hollow chamber 66. The pressurized gas presses the skin layer of the partition outer peripheral portion 54 against the inner surface of the mold 67, and in this state, the solidification of the resin inside the skin layer proceeds, so that the dimensional accuracy of the partition outer peripheral portion 54 is increased. Can be prevented from being reduced due to the influence of sink during solidification of the resin, and the outer peripheral portion 54 of the partition wall can be formed into a shape exactly corresponding to the cavity shape of the mold 67.

In particular, by blowing a pressurized gas into the mold 67 at a timing such that a circumferential surface portion 66A substantially parallel to the outer peripheral surface 54A is formed in the hollow chamber 66 as in the present embodiment, the outer periphery of the partition wall is formed. Since the thickness of the portion along the outer peripheral surface of the portion 54 can be made uniform, the influence of local coagulation shrinkage is reduced, and the outer diameter dimensional accuracy of the partition outer peripheral portion 54 is improved.

Further, by changing the conditions for injecting the resin into the mold 67 and the conditions for blowing the gas into the mold 67 during the injection molding,
Since the thickness of the partition outer peripheral portion 54 can be adjusted, a plurality of types of partition members 50 having different thicknesses of the partition outer peripheral portion 54 can be manufactured using the mold 67 having the same shape.

In the vibration isolator 40 of the present embodiment, the partition member 50 is formed by the partition peripheral portion 54 and the membrane rubber 55. However, under the condition that the vibration level in the high frequency range is low, the partition member 50 as a whole is made of resin. A sufficient vibration damping effect can be obtained even when the partition member 50
By forming a hollow chamber along the outer peripheral surface inside the
The dimensional accuracy of the outer peripheral surface of the partition member 50 can be improved.

(Second Embodiment) FIGS. 5 to 7 show a vibration damping device according to a second embodiment of the present invention, and the present invention is applied to a so-called bush type vibration damping device. In the figure, reference symbol O indicates a center line, and a direction along the center line is an axial direction. The vibration isolator 80 includes a mounting frame 81 for connection to a vehicle body (not shown).
Inside the annular portion 82 of the mounting frame 81, a cylindrical outer tube fitting 83 is disposed.

The outer peripheral portion of a thin rubber-made first diaphragm 84 is vulcanized and bonded to the inner peripheral surface of the outer cylindrical fitting 83. As shown in FIG. 5, the first diaphragm 84 is arranged at an upper portion inside the outer tube fitting 83, and forms an air chamber 85 between the first diaphragm 84 and the outer tube member 16. The air chamber 85 is communicated with the outside as needed.

An intermediate cylinder 86 and an intermediate block 87 are inserted into the outer cylinder fitting 83, and the intermediate block 87 is formed as a partition member.

The intermediate block 87 is formed in a substantially semicircular block shape when viewed from the axial direction of the outer cylinder fitting 83. As shown in FIG.
3 is in close contact with the inner peripheral surface. As shown in FIG. 7, circular flanges 86A are formed at both ends in the axial direction of the intermediate cylinder 86 in the radial direction, and an intermediate block 87 is fitted between the pair of flanges 86A. The outer peripheral surfaces of the pair of flange portions 86A are respectively provided with outer cylinder fittings 83.
Is tightly adhered to the inner peripheral surface.

The intermediate portion of the intermediate cylinder 86 in the axial direction is a substantially U-shaped plate 86F which opens downward as shown in FIG. 5, and both ends of the plate 86F are respectively connected to the flange 86A. It is fixed. Plate 8
The U-shaped open portion 86B of 6F is opposed to a flat portion 87B serving as the upper surface of the intermediate block 87, and an inner cylindrical fitting 88 connected to an engine (not shown) penetrates the open portion 86B. The inner tube member 88 is arranged coaxially with the outer tube member 83 when the engine is mounted, and is therefore non-coaxial in FIGS. An elastic body 89 formed of a rubber material or the like is stretched between the intermediate cylinder 86 and the intermediate cylinder 86. Due to this elastic body 89, the inner cylinder fitting 88 is changed to the outer cylinder fitting 83.
Can be moved relative to.

As shown in FIG. 5, the elastic body 89 extends from the inside of the open portion 86B to the outer peripheral surface of the plate 86F in the intermediate cylinder 86 to become a thin elastic body 89A.
F covers the outer peripheral surface. The outer peripheral surface of the intermediate cylinder 86 is in close contact with the inner peripheral arc surfaces 87A at both axial ends of the intermediate block 87 via the thin elastic body 89A. Also, the elastic body 89
A notch 89 which is an intermediate portion in the axial direction and is recessed in a V-shape toward the axis of the inner cylindrical fitting 88 below the inner cylindrical fitting 88.
A is formed, and a space between the notch 89A and the plane portion 87B of the intermediate block 87 is a main liquid chamber 90. On the other hand, a space is formed between the pair of flange portions 86 </ b> A of the intermediate cylinder 86 by the intermediate cylinder 86 and the first diaphragm 84, and this space is a first auxiliary liquid chamber 91. The cavity 86C between the opening 86B and the elastic body 89 penetrates in the axial direction as shown in FIG.

As shown in FIG. 7, the intermediate block 87
Are formed on the outer peripheral surface thereof, each of which extends in the circumferential direction and has a different width in the axial direction, and the outer circumferences of these grooves 92 and 93 are closed by an outer cylinder fitting 83. One end of each of the grooves 92 and 93 opens to one end (right end of the intermediate block 87 shown in FIG. 5) 87C of the intermediate block 87 to open the first sub liquid chamber 91.
It is connected to. Here, the narrow width of the groove portion 92 corresponds to that of FIG.
As shown in the figure, the intermediate block 87 is curved in a U-shape in the vicinity of the end 87D of the intermediate block 87 on the opposite side to the end 87C.
Folded in the direction of. The intermediate block 87 is formed with a through hole 94 penetrating from the plane portion 87 </ b> B to the inner surface of the groove 92, and the other end of the groove 92 communicates with the main liquid chamber 90 via the through hole 94. The liquid passage formed by the groove 92 and the outer cylindrical member 83 and the through hole 94 communicate the main liquid chamber 90 and the first sub liquid chamber 91 to form a shake orifice 95 as a restriction passage for absorbing shake vibration. are doing.

As shown in FIGS. 5 and 9, a circular hole 96 is formed on the side of the plane portion 87B of the intermediate block 87.
At the bottom of the circular hole 96, a circular through hole 97 having a smaller diameter than the circular hole 96 and penetrating the outer peripheral surface of the intermediate block 87 is formed coaxially with the circular hole 96. A counterbore 98 having a larger diameter than the circular through-hole 97 is provided coaxially with the circular through-hole 97 on the outer cylinder fitting 83 side of the intermediate block 87. Further, on the outer peripheral surface of the intermediate block 87, an annular groove 98A is provided around the axis of the circular through hole 97 outside the counterbore 98, and an O-ring 99 for sealing is fitted into the groove 98A. .

On the other hand, as shown in FIG. 5, a pair of passages 100 and 101 are formed inside the intermediate block 87 along the radial direction of the circular hole 96 in opposite directions. One passage 100 extends from the inner peripheral surface of the circular hole 96 to the intermediate block 8.
7, and extends toward the end 87C side of the intermediate block 87.
Is connected to the groove 92 on the outer peripheral surface of the outer peripheral surface. The other passage 101 extends from the inner peripheral surface of the circular hole 96 toward the end 87D side of the intermediate block 87, and opens into a recess 115 provided on the outer peripheral surface of the intermediate block 87. The concave portion 115 is curved in an arc shape along the outer peripheral surface of the intermediate block 87, and has a groove 1 for fixing the diaphragm on its outer peripheral edge.
15A (see FIG. 9). The outer periphery of the second diaphragm 103 is formed in a rib shape corresponding to the groove 115A, and the outer periphery is formed in the groove 115 over the entire periphery.
A, and is fixed by being sandwiched and fixed between the intermediate block 87 and the inner peripheral surface of the outer cylinder fitting 83.
A second sub-liquid chamber 102 communicating with the outer cylinder 01 and a second air chamber 104 facing the outer tube fitting 83 are formed. The second diaphragm 103 is curved so as to be convex toward the inside of the recess 115, and forms the second sub-liquid chamber 102 between the second diaphragm 103 and the recess 115, and is used for the second sub-liquid chamber 102. An elastically deformable partition is formed. Further, the second diaphragm 103 forms a second air chamber 104 in which gas is sealed between the second diaphragm 103 and the inner peripheral surface of the outer cylinder fitting 83, and the second air chamber 104 is a second diaphragm. 103 can be modified. Here, the second diaphragm 103 is configured such that the area is smaller than the area of the first diaphragm 84 and the rigidity is larger than the rigidity of the first diaphragm 84.

The main liquid chamber 90, the first sub liquid chamber 91, and the second sub liquid chamber 102 described above are filled with a liquid such as ethylene glycol.

The intermediate block 87 has a circular hole 9 inside.
A hollow chamber 130 is formed adjacent to 6. The hollow chamber 130 is formed below the flat portion 87B, and as shown in FIG.
The hollow space 130 is formed with a circumferential surface portion 130 </ b> A that expands in the circumferential direction along the inner circumferential surface of the circular hole 94. Further, as shown in FIG. 9, the hollow chamber 130 has a flat surface formed on the flat
A substantially triangular shape is formed along the arc surface and along the inner peripheral surface of the circular hole 96, and the circumferential surface portion 130 </ b> A of the hollow chamber 130 is located at a position slightly deeper than the lower end of the circular hole 96 from near the upper end of the circular hole 96. Extends to Here, the hollow chamber 130 does not interfere with the passages 100 and 101 inside the intermediate block 87, and extends from the inner peripheral surface of the circular hole 96 to the side end surface of the intermediate block 87 in the axial direction (vertical direction in FIG. 8). In a state where the distance is the longest, that is, in a state where the hollow chamber 96 is not formed, it is provided in a part where the wall thickness is the largest at the peripheral part of the circular hole 96. The hollow chamber 130 is formed with a gas injection hole 131 penetrating from the top to the plane portion 87B. Therefore, the hollow chamber 130 is provided with the gas injection hole 13.
The hollow chamber 130 is filled with the liquid in the main liquid chamber 90 by communicating with the main liquid chamber 90 via the first liquid chamber 1.

The intermediate block 87 is integrally formed of a low-hygroscopic resin, and the resin used as a material of the intermediate block 87 is a resin that suppresses sliding resistance to the rotary valve 105 and that is formed during injection molding described later. Adopt one with excellent properties. As such a resin, for example,
Poniphenylene sulfide (PPS), liquid crystal polymer,
Fluororesin, polybutylene terephthalate (PBT),
Either thermoplastic polymer is employed.

A rotary valve rotor 105 is rotatably inserted into the circular hole 96 and the circular through hole 97 of the intermediate block 87. A large-diameter cylindrical portion 105A having an open upper end surface is provided above the rotary valve 105, and a small-diameter shaft portion 105B is provided on the opposite side of the cylindrical portion 105A.
5A is provided coaxially and integrally. Further, as shown in FIG. 8, a rectangular recess 87E having an upper end portion of the circular hole 96 as a bottom surface is formed in the flat portion 87B of the intermediate block 87.
A square plate-shaped washer 106 is fitted into and fixed to the concave portion 87E as shown in FIG. The washer 106 is moved to a position corresponding to the circular hole 96,
A circular opening 106A having a smaller diameter than the circular hole 96 is formed. The washer 106 allows the inner space of the cylindrical portion 105A of the rotary valve 105 to communicate with the main liquid chamber 90 by the circular opening 106A. 96 is prevented from falling off. Also, the shaft 10 of the rotary valve 105
A pair of annular grooves are formed on the outer periphery of 5B, and a pair of O-rings 120 are fitted in the pair of annular grooves, respectively. The O-ring 107 allows the circular through hole 9 to be formed.
7 is prevented from leaking.

In the cylindrical portion 105A of the rotary valve 105,
A through hole 107 communicating between the inside and outside of the cylinder is formed in the outer peripheral portion. The through holes 107 are formed in the circular holes 96 of the passages 100 and 101.
As shown in FIG. 5, when the rotary valve 105 rotates to a predetermined first position and the through-hole 107 faces the passage 100, as shown in FIG. The liquid chamber 90 and the first sub liquid chamber 91 are communicated via the passage 100 and the groove 92. At this time, the passage 100 and the groove 92 communicating the main liquid chamber 90 and the first sub liquid chamber 91 are connected.
Constitutes an idle orifice 108 serving as a restriction passage for absorbing idle vibration.

As shown in FIG. 6, the rotary valve 1
05 rotates to a predetermined second position and the through-hole 107 faces the passage 101, the main liquid chamber 90 and the second sub-liquid chamber 102
Are communicated through the passage 101. At this time, passage 1
Reference numeral 01 designates a muffled orifice 109 serving as a restriction passage for absorbing muffled sound.

In the vibration isolator 80 having the above structure, when the rotary valve 105 is rotated to the first position by the motor 110 as shown in FIG.
The main liquid chamber 90 and the first sub liquid chamber 91 communicate with each other via the. In addition, the rotary valve 105 is rotated by approximately 180 ° from the first position.
When the rotary valve 105 is rotated to the second position as shown in FIG. 6, the through hole 38 of the cylindrical portion 36A is rotated.
When the confined orifice 62 is opened, the main liquid chamber 30 and the second sub liquid chamber 102 are communicated via the confined orifice 62.

The motor 70 is connected to the controller 112 as shown in FIG.
The rotation is controlled by this. The controller 112 receives detection signals from at least the vehicle speed sensor 113 and the engine speed detection sensor 114, detects the vehicle speed and the engine speed, respectively, and can determine whether idle vibration or shake vibration occurs.

Next, the vibration isolator 8 configured as described above is used.
The method of manufacturing the intermediate block 87 at 0 will be described. The intermediate block 87, which is a partition member, is integrally formed of resin as described above, and the same injection molding machine as that of the first embodiment can be used during manufacturing. A mold (not shown) having a different cavity shape and the like from the case of the first embodiment is mounted.

The molding die of the intermediate block 87 has an assembling structure that can be disassembled into a plurality of parts so that a molded product can be taken out. This mold has an intermediate block 87
Is formed, and an open gate is provided at a position corresponding to the gas injection hole 131. The mold has a circular hole 94 which constitutes a valve body storage chamber.
A two-stage cylindrical core corresponding to the shape of the circular through hole 95, a prismatic core corresponding to the shape of the passages 100 and 101, and the like are set.

An injection nozzle (see FIG. 4) is connected to the gate of the mold mounted on the injection molding machine. Injection molding machine
First, a molten resin is injected into a mold through a gate. At this time, the injection amount of the resin into the mold is determined by a filling rate of the resin with respect to a predetermined volume of the cavity. The resin injected into the cavity begins to solidify from the part in contact with the inner surface of the cavity and the outer peripheral surface of the core due to the endothermic reaction by the mold, and a skin layer is formed along the cavity and the core, and this skin layer is formed over time. The thickness increases.
An unsolidified molten layer is sealed inside the skin layer.

The injection molding machine injects pressurized gas into the cavity through the gate at the timing when the skin layer in the cavity has a constant thickness. The pressurized gas flows so as to push the central portion of the molten layer, which has the slowest solidification, toward the cavity and the core, thereby forming the hollow chamber 130. The injection molding machine holds the gas filled in the hollow chamber 130 at a predetermined pressure until the resin in the cavity is substantially completely solidified,
After the solidification is completed, the nozzle is released from the mold. Thereafter, the mold is disassembled into a plurality of parts, so that the intermediate block 87 integrally formed of resin can be taken out.
6. The circular through hole 97 and the passages 100 and 101 are opened. A hollow chamber 130 is formed inside the intermediate block 87 as shown in FIGS.

Next, the operation of the vibration isolator 80 according to this embodiment will be described.

When the engine connected to the inner cylinder 88 is operated, the vibration of the engine is transmitted to the elastic body 89 via the inner cylinder 88. The elastic body 89 acts as a vibration absorber, and the vibration is absorbed by a vibration damping function based on internal friction of the elastic body 89. Further, the liquid in the main liquid chamber 90 and the first sub liquid chamber 91 whose internal volumes change with the deformation of the elastic body 89 and the first diaphragm 84 is displaced by the shake orifice 95.
The liquid in the main liquid chamber 30 and the first sub liquid chamber 91, whose internal volumes change with the deformation of the elastic body 89 and the first diaphragm 84, flow through the idle orifice 10
8, the main liquid chamber 90 whose internal volume changes with the deformation of the elastic body 89 and the second diaphragm 103.
And the liquid in the second sub liquid chamber 102 mutually flows through the orifice 109 for confinement, and the vibration damping effect is improved by viscous resistance of the liquid flow generated in these orifice spaces and damping action based on liquid column resonance. can do.

In addition to the shake orifice 95 which is always open, an idle orifice 108 and an orifice 109 are provided, and a rotary valve 105 for connecting the main liquid chamber 90 to one of the orifices 108, 109 is provided. The following operation is achieved.

When the vehicle runs at a high speed of, for example, 70 to 80 km / h or more, shake vibration (less than 15 Hz) occurs. The controller 112 determines, based on signals from the vehicle speed sensor 113 and the engine speed detection sensor 114, whether or not shake vibration has occurred. When the controller 112 determines that the shake vibration is occurring, the controller 112 operates the motor 110 to rotate the rotary valve 105 to the second position. As a result, as shown in FIG. 6, the idle orifice 108 is closed, and the shake orifice 95 which is always open is divided into the main liquid chamber 90 and the first sub liquid chamber 91.
And the orifice 109 for communication between the main liquid chamber 90 and the second sub liquid chamber 102. As a result,
The pressure change based on the engine vibration generated in the main liquid chamber 90 is caused by the shake orifice 95 and the squeezing orifice 109.
In addition to being transmitted to the liquid inside, the shake vibration is absorbed by the resistance and the like of the liquid.

Further, a muffled sound (50 to 10) which is a high-frequency and small-amplitude vibration which may be generated together with the shake vibration.
For 0 Hz), the liquid column resonates in the muffled orifice 109 to lower the dynamic spring constant, and muffled sound is absorbed.

When the engine is idling or the vehicle speed is 5 km / h or less, idle vibration (20 to
40 Hz). The controller 112 is a vehicle speed sensor 1
13. It is determined by the engine speed detection sensor 114 whether idle vibration has occurred. When the controller 112 determines that idle vibration has occurred, the controller 1
12 rotates the motor 110 to the second position, and makes the through hole 38 of the rotor 36 correspond to the idle orifice 60 as shown in FIG. As a result, as shown in FIG. 5, the orifice 109 is closed and the liquid flows through the main liquid chamber 9 through the idle orifice 108 having a small passage resistance.
It moves between 0 and the first sub liquid chamber 91, and the liquid column resonates in the idle orifice 108, the dynamic spring constant decreases, and the vibration is absorbed.

Further, since the shake orifice 95 connecting the main liquid chamber 90 and the first sub liquid chamber 91 is always open, the liquid can flow to the shake orifice 95 side. As a result, the first diaphragm 84 can be deformed by a low-frequency vibration similar to the shake vibration that may be generated together with the vibration of the idle vibration. Therefore, the first diaphragm 84 is deformed, and the vibration in the low frequency range, which may be generated simultaneously with the vibration of the idle vibration, is transmitted to the shake orifice communicating between the main liquid chamber 90 and the first sub liquid chamber 91. It can be attenuated by 95.

According to the vibration isolator 80 of the present embodiment described above, the intermediate block 87, which is a partition member, is integrally formed of resin, and the inside of the intermediate block 87 is adjacent to the circular hole 96, which is a valve housing chamber. By forming the hollow chamber 130, the thick portion around the circular hole 96 is
Therefore, when the intermediate block 87 is molded by a mold, it is possible to prevent the dimensional accuracy of the inner diameter of the circular hole 96 from being reduced by the influence of sink at the time of resin solidification, and to the periphery of the circular hole 96. Since the opening to the outer surface of the intermediate block 87 is only the gas injection hole 131 as compared with the case of forming a recess such as a groove shape, a decrease in the strength of the peripheral portion of the circular hole 96 can be suppressed. As a result, the sealing performance between the inner peripheral surface of the circular hole 96 and the outer peripheral surface of the cylindrical portion 105A of the rotary valve 105 is improved, so that the liquid leaks from between the circular hole 96 and the cylindrical portion 89A of the rotary valve 89. That is, liquid leakage between the main liquid chamber 90 and the idle orifice 105 and between the main liquid chamber 90 and the confined ru orifice 109 are prevented.

Further, according to the method of manufacturing the vibration isolator 80 of the present embodiment, the heat-melted resin is injected into the mold to form a skin layer which is an initial solidified layer of the intermediate block 87, Pressurized gas is blown into the molten layer inside the layer, and a hollow chamber 130 is formed in the intermediate block 87 so as to be adjacent to the circular hole 96, so that a thick portion at the periphery of the circular hole 96 is thinned by the hollow chamber 130. And the skin layer around the circular hole 96 is pressed against the inner surface of the mold by the pressurized gas blown into the hollow chamber 130,
In this state, solidification of the resin inside the skin layer progresses,
It is possible to prevent the dimensional accuracy of the circular hole 96 from being reduced by the influence of sink during solidification of the resin, and to form the circular hole 96 into a shape that exactly corresponds to the shape of the cavity (core) of the mold.

In particular, as in this embodiment, the hollow chamber 130
By blowing a pressurized gas into the mold at a timing such that a circumferential surface portion 130A substantially parallel to the inner circumferential surface of the circular hole 96 is formed, the thickness of the partition between the hollow chamber 130 and the circular hole 96 is increased. Since the thickness can be made uniform, the influence of local coagulation shrinkage is reduced, and the dimensional accuracy of the inner diameter of the circular hole 96 is improved.

By changing the conditions for injecting the resin into the mold during injection molding and the conditions for blowing the pressurized gas,
Since the thickness of the partition between the hollow chamber 130 and the circular hole 96 can be adjusted, a plurality of types of the partition walls between the hollow chamber 130 and the circular hole 96 having different thicknesses can be formed by using a mold having the same shape. The intermediate block 87 can be manufactured.

In the second embodiment, the outer cylinder 83 is attached to the vehicle body, and the inner cylinder 88 is attached to the engine.
Although the configuration is such that the side is attached, the configuration may be reversed. FIGS. 8 and 9 show portions where the hollow chamber 130 is provided.
And the number of hollow chambers 130 is not limited to one. Therefore, for example, a plurality of hollow chambers may be formed so as to surround a portion of the circular hole 96 except for a connection portion with the passages 100 and 101.

In the vibration isolator 80 of the second embodiment,
The rotary valve 105 is rotated by the motor 110 to switch the orifices 108 and 109 communicating with the main liquid chamber 90. However, the valve inserted into the circular hole 96 and the circular through hole 97 serving as the valve body storage chamber. The body is a rotary valve 10
For example, the orifice 1 reciprocates inside the circular hole 96 and the circular through hole 97 and communicates with the main liquid chamber 90.
A piston valve for switching between 08 and 109 may be used.

[0074]

As described above, according to the vibration isolator of the present invention, it is possible to reduce the thickness of the partition wall member where high dimensional accuracy is required, and to reduce the strength of the partition wall member by reducing the thickness. Reduction is suppressed.

Further, according to the method of manufacturing a vibration isolator of the present invention, it is possible to form a thick portion of a partition wall member with high dimensional accuracy without changing a mold shape for injection molding.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a vibration isolator according to a first embodiment of the present invention.

FIGS. 2A and 2B are a plan view and a side cross-sectional view illustrating a partition member in the vibration isolator according to the first embodiment of the present invention.

FIG. 3 is a side sectional view showing a mold for manufacturing a partition member in the vibration isolator according to the first embodiment of the present invention, and a membrane rubber set in the mold.

FIG. 4 is a cross-sectional view showing an injection molding nozzle for manufacturing the partition member according to the first embodiment of the present invention and a solidified state of a resin injected into a mold by the nozzle.

FIG. 5 is a cross-sectional view showing a vibration isolator according to a second embodiment of the present invention, showing a state in which a main liquid chamber is communicated with an orifice for confining by a rotary valve.

FIG. 6 is a cross-sectional view illustrating a vibration isolator according to a second embodiment of the present invention, showing a state where a main liquid chamber is communicated with an idle orifice by a rotary valve.

FIG. 7 is an exploded perspective view showing an exploded view of a mounting frame, an outer cylinder fitting, an intermediate cylinder, and an intermediate block in a vibration isolator according to a second embodiment of the present invention.

FIG. 8 is a plan view showing an intermediate block in a vibration isolator according to a second embodiment of the present invention.

FIG. 9 is a side cross-sectional view showing an intermediate block in a vibration isolator according to a second embodiment of the present invention.

FIG. 10 is a sectional view showing an example of a conventional vibration damping device.

11A and 11B are a plan view and a side sectional view showing a partition member in the vibration isolator shown in FIG.

12 is a side sectional view showing a mold for manufacturing a partition member in the vibration isolator shown in FIG. 10, and a membrane rubber set in the mold.

[Explanation of symbols]

 40 Vibration isolator 41 Connecting member (first mounting member) 42 Mounting bracket (first mounting member) 43 Screw (first mounting member) 44 Lid member (second mounting member) 45 Screw (second mounting) 46) outer cylinder (second attachment member) 47 elastic body 49 liquid chamber 50 partition member 51 main liquid chamber 52 sub liquid chamber 54 partition outer peripheral part 55 membrane rubber 65 restriction passage 66 hollow chamber 67 mold 73 nozzle 80 vibration isolation Apparatus 81 Mounting frame (first mounting member) 82 Annular portion (first mounting member) 83 Outer tube fitting (first mounting member) 86 Intermediate tube 87 Intermediate block (partition member) 88 Inner tube fitting (second member) Attachment member) 89 Elastic body 90 Main liquid chamber 91 First sub liquid chamber 92, 93 Groove (restricted passage) 96 Circular hole (valve housing) 97 Circular through hole (valve housing) 100, 101 Passage (restricted) Passage) 105 b Tariben (valve body) 107 through hole (restricted passage) 95,108,109 orifice 130 hollow chamber

 ──────────────────────────────────────────────────の Continued on the front page F term (reference) 3D035 CA05 CA35 3J047 AA03 CA12 CB09 DA01 FA02 GA01 4F206 AA16 AA25 AA34 AA45 AE07 AH16 JA05 JA07 JB12 JN27 JQ81

Claims (4)

[Claims] A first mounting member connected to one of the vibration generating section and the vibration receiving section; a second mounting member connected to the other of the vibration generating section and the vibration receiving section; and the first mounting section An elastic body that connects the member and the second mounting member; a liquid chamber in which at least a part of an inner wall is formed of the elastic body and in which a liquid is sealed; A main liquid in which a hollow chamber extending along the inner wall of the liquid chamber is formed in an outer peripheral portion, and the outer peripheral portion is brought into close contact with the inner wall of the liquid chamber to change the inner volume of the liquid chamber by deformation of the elastic body. A vibration isolator, comprising: a partition member partitioned into a chamber and a sub liquid chamber adjacent to the main liquid chamber; and a restriction passage communicating the main liquid chamber and the sub liquid chamber. 2. A first mounting member connected to one of the vibration generator and the vibration receiver, a second mounting member connected to the other of the vibration generator and the vibration receiver, and the first mounting. An elastic body that connects the member and the second mounting member; a liquid chamber in which at least a part of an inner wall is formed of the elastic body, and in which a liquid is sealed; and an outer peripheral portion in close contact with an inner wall of the liquid chamber. A partition member that divides the liquid chamber into a main liquid chamber whose internal volume changes due to deformation of the elastic body and a sub liquid chamber adjacent to the main liquid chamber; and communicates the main liquid chamber with the sub liquid chamber. And forming a skin layer corresponding to the outer shell of the partition member after injecting the heated and melted resin into the mold,
Pressurized gas is blown into the molten layer inside the skin layer to form a hollow chamber extending along the inner wall of the liquid chamber in the partition member. 3. An outer cylinder connected to one of the vibration generator and the vibration receiver and formed into a cylindrical shape, and connected to the other of the vibration generator and the vibration receiver and disposed inside the outer cylinder. An inner cylinder, an elastic body disposed between the outer cylinder and the inner cylinder, and a main body in which a liquid is sealed with the elastic body as a part of a partition wall and the inner volume is changed by deformation of the elastic body. A liquid chamber, a sub-liquid chamber that is isolated from the main liquid chamber and is filled with a liquid, a restriction that separates the main liquid chamber and the sub-liquid chamber, and that connects the main liquid chamber and the sub-liquid chamber. A partition member provided with a passage and having a valve body storage chamber formed in the middle of the restriction passage; and a liquid flow inserted between the valve body storage chamber and the main liquid chamber and the sub liquid chamber being controlled. And a valve member, wherein at least a periphery of the valve member storage chamber in the partition member is made of a resin material. Molded, vibration damping device, characterized in that the formation of the cavity in the vicinity of the valve body accommodating chamber in the interior of the partition member by. 4. An outer cylinder connected to one of the vibration generating section and the vibration receiving section and formed in a cylindrical shape, and connected to the other of the vibration generating section and the vibration receiving section and arranged inside the outer cylinder. An inner cylinder, an elastic body disposed between the outer cylinder and the inner cylinder, and a main body in which a liquid is sealed with the elastic body as a part of a partition wall and the inner volume is changed by deformation of the elastic body. A liquid chamber, a sub-liquid chamber which is isolated from the main liquid chamber and in which a liquid is sealed, and which separates the main liquid chamber and the sub-liquid chamber and communicates the main liquid chamber with the sub-liquid chamber. A partition member provided with a restriction passage and a valve body storage chamber formed in the middle of the restriction passage; and a flow of liquid between the main liquid chamber and the sub liquid chamber inserted into the valve body storage chamber. Controlling the valve element, comprising: injecting the heated and melted resin material into the mold. A skin layer corresponding to the outer shell of the partition member is formed, and a pressurized gas is blown into a molten layer inside the skin layer to form a hollow chamber near the valve body storage chamber inside the partition member. A method for manufacturing a vibration isolator.